We shall evaluate different types of narcotic antagonists, as these may become available, to determine a) the optimal method of using them clinically, in relation to dose, dosage, duration of treatment, follow up and feasibility of these approaches to treating opiate dependent individuals; b) to determine the toxicity of these agents in terms of side effects, both acute and chronic; c) to test the possible therapeutic employment of these drugs in a program of deconditioning to drug use. Such phase 1 and 2 clinical testng of these agents will be done in a variety of populations of patients. In addition, it is our intention to pre-test protocols for the controlled study of narcotic antagonists in multiclinic trials and to train personnel engaged in such trials in the use of the drugs involved and the procedures of the experimental protocol. The first drugs which will be studied under this program are propranolol and naltrexone, but it is anticipated that others will be looked at as they become available for clinical testing. A series of studies, already underway, will investigate the potential use of propranolol in treating opiate withdrawal and as a possible maintenance treatment for patients, either alone or combined with methadone. Naltrexone will be used primarily as a maintenance treatment, either as the primary treatment or as a replacement for methadone maintenance. It may also be employed in some patients not fully dependent upon opiates but at high risk of becoming so. Each of these pharmacological approaches to the management of these patients will be done within the framework of a total rehabilitative program including psychological, social and vocational rehabilitative techniques.